NEETPhysicsCurrent Electricity
A uniform wire AB of resistance 12 is connected to a battery of EMF 26 V and internal resistance 2 . A resistor R = 12 is connected between end A and a point C on the wire, such that the length AC is 1 3 of the total length AB. What is the electrical power dissipated in the resistor R ?
Options
- A4.2 W
- B3 W
- C9 W
- D12 W
Correct answer
B. 3 W
Step-by-step solution
The resistance of the wire is proportional to its length. The resistance of segment AC is 1 3 12 = 4 , and the resistance of segment CB is 2 3 12 = 8 . The external resistor R = 12 is connected in parallel with the segment AC. The equivalent resistance of this parallel combination is: R_ AC = 12 4 12 + 4 = 48 16 = 3 The total resistance of the circuit includes R_ AC , the remaining wire segment CB, and the internal resistance of the battery: R_ total = R_ AC + R_ CB + r = 3 + 8 + 2 = 13 The total current drawn from